Research On Passive Buoyancy Compensation Method And Technology Of Underwater Vehicle

As an important platform for ocean detection,underwater robot has the advantages of long range,deep diving,low power consumption and intelligence,and has become the trend of development in the future.During the operation of the underwater vehicle,buoyancy will increase as the increased density of the water in the vertical direction.However,due to the pressure of seawater,the compression deformation of the pressure hull will cause the buoyancy of the carrier to decrease.Therefore,the mismatch between the carrier and the compressibility of the sea water will result in a corresponding change in the net buoyancy of the underwater vehicle,which will affect its running state.In this paper,the passive buoyancy compensation technology of underwater vehicle is studied.The compressibility of liquid is used to match the overall compressibility of the carrier with the compressibility of seawater,and the buoyancy loss of the operation is compensated passively.The main contents of this paper are as follows:1.Research on passive buoyancy compensation method.Through the study of the factors affecting the buoyancy of the underwater vehicle,a passive buoyancy compensation method based on compressible liquid is proposed.And then the suitable compressible liquid is selected as the compensating liquid and the formula for calculating the volume and amount of the compensated liquid is derived.2.The design of measuring device for bulk modulus and the experiment of the compressibility coefficient measurement.On the basis of theory analysis on bulk modulus of oil,the measuring scheme based on the definition of bulk modulus is proposed.The method of theoretical analysis and calculation and finite element simulation by Workbench software are used to check and analyze the measuring error.The concept of comprehensive compression coefficient is put forward.The experiment of compressibility liquid compressibility coefficient is completed by measuring device,and the comprehensive expression of the compressibility coefficient of the compressible fluid is obtained through the analysis and fitting.3.Application of passive buoyancy compensation technology.The passive buoyancy compensation technique is applied to the underwater glider and the passive buoyant compensator is designed.Applying the finite element to analyze the deformation of compressive cabin,and the compensation of the passive buoyancy and the minimum amount of active buoyancy adjustment are calculated,and the energy consumption is analyzed by the loss of buoyancy.